Snow and freezing rain made for perilous driving conditions on Christmas Day in Oklahoma, where 21 cars piled up in Oklahoma City before the massive winter storm spread east into Arkansas.

A downtown OKC street on Christmas morning

Blizzard warnings were issued in southwest Oklahoma and northeast Arkansas, where forecasters said strong winds could create blowing snow conditions that are rarely seen in Arkansas.

“Highway travel is strongly discouraged,” the Oklahoma Department of Transportation said in a news release.

The pileup in Oklahoma City began about 3 a.m. when a semitrailer jackknifed on Interstate 40 on a bridge over the Oklahoma River, state Highway Patrol Trooper Betsy Randolph said. Other vehicles hit the semi and other semis slid into the vehicles, sandwiching them, she said.

In all, there were 10 separate crashes involving 21 vehicles and three tractor-trailers. Several people were injured.

“Some of them, it took the entire top of the car off, like they slid under a semi,” Randolph said.

Officials were able to reopen I-40 after about five hours, but roads in numerous areas of Oklahoma were slick with ice, according to the highway department.

Also Tuesday, crews treated bridges on Interstate 35 south of Oklahoma City, and icy conditions made driving difficult near Tulsa. In western Oklahoma, officials reported slick and hazardous conditions on I-40 in Beckham, Washita and Custer counties due to sleet and blowing snow.

Officials cautioned as temperatures fell during the day, roads that had been wet were likely to freeze.

In Arkansas, up to 10 inches of snow was forecast through Wednesday in the northeast part of the state, which was under a blizzard warning. In Little Rock and much of central and northern Arkansas, 3 to 6 inches of snow was forecast, with higher amounts in the Ozark and Ouachita mountains.